This invention concerns an automatic gunning apparatus for the repair of metallurgical furnaces which has a detachably mounted gunning pipe. More specifically, it concerns an automatic gunning apparatus for repairing the refractory lining of metallurgical furnaces such as converters and electric furnaces, the whole apparatus being compact and so designed that the gunning pipe can be freely attached and detached.
Conventionally, the repair by gunning pipe of the amorphous refractory lining of converters and electric furnaces used for steelmaking has been carried out by the following methods:
(1) Insertion of a gunning pipe into the furnace by a skilled operator who carries out the gunning operation manually, or PA1 (2) Operation by remote control of an automatic gunning apparatus equipped with a gunning pipe which is water cooled and which has a mechanism for elongating and contracting the pipe.
In method (1), i.e., manual repair, the operator must carry the heavy gunning pipe for a long period of time in order to insert it into the furnace at high temperature and perform the gunning operation under high temperature conditions, which requires great muscular effort.
In method (2), the apparatus is usually mounted on a self-propelled vehicle, the gunning pipe being water cooled and having a mechanism by which it can be elongated or contracted, so that the gunning operation can be performed by remote control. In this case, however, the apparatus is bulky, while the mechanism is complex and costly. In particular, although the gunning pipe has a mechanism by which it may be elongated or contracted, its overall length when contracted is still considerable, so its manipulation, operation and control in a narrow space is complicated and requires experience. Further, a large space is required to store the apparatus when it is on standby for operation. In addition, although the gunning pipe is enclosed in a water-cooled tube, it deforms due to wear and heat and often has to be replaced. The replacement operation, moreover, is tedious and requires a great deal of preparation.
The present invention therefore aims to solve these problems inherent in the prior art. More specifically, it aims to provide an automatic gunning apparatus of simple structure for repairing metallurgical furnaces which has a detachably mounted gunning pipe and which can accommodate a gunning pipe of simple structure such as the gunning pipe generally used for manual repair operations in the past.
A further object of the present invention is to provide an automatic gunning apparatus for repairing metallurgical furnaces which has a detachably mounted gunning pipe, wherein the gunning pipe can be freely mounted and detached, the pipe being mounted on the apparatus at the beginning of the gunning operation, the operation being carried out by remote control, and the pipe detached from the apparatus when the operation has been completed.